1. Field of the Invention
This invention relates to an image pick-up apparatus arranged to convert an optical image of an object to be photographed into an electrical image signal by means of an image sensor such as a CCD and to record a still picture signal on a recording medium such as a rotary magnetic disc or the like and more particularly to an image pick-up apparatus which is capable of reproducing the recorded signal.
2. Description of the Related Art
There is known an electronic camera system of the kind arranged to convert an optical image of an object into an electrical image signal by means of an image sensor such as a CCD, to divide the signal into a luminance signal and a chrominance signal, to perform a signal processing operation such as frequency modulation, etc. and to record the processed signal on a recording medium such as a rotary magnetic sheet or disc or the like.
The electronic camera system of the abovestated kind features that the image recorded on the recording medium can be immediately reproduced on a display device such as a CRT by applying it to a reproducing apparatus or can be printed into a hard copy by a printer without subjecting the medium to any intermediate process.
It is conceivable that, in reproducing an image recorded by the above-stated electronic camera system, the reproduction can be accomplished by the camera system itself without recourse to any reproducing apparatus. An electronic camera embodying such a concept reproduces the recorded image by utilizing, as they are, a drive device for driving the recording medium, a magnetic head and a driving part provided for driving it. FIG. 5 of the accompanying drawings shows in a block diagram the arrangement of the electronic camera which is capable of performing a reproducing operation as well as recording.
Referring to FIG. 5, an optical system block 1 includes a photo-taking lens 1a, a diaphragm 1b and a shutter 1c. The light of an object to be photographed passes through the block 1 to form an image on the image pick-up surface of a CCD 2. The image is then converted into an electrical image signal. The image signal which is thus produced from the CCD 2 is divided at a signal processing circuit 3 into a luminance signal and a chrominance signal. The signal is further processed into a form suited for recording, e.g. into a frequency modulated signal or the like. The processed signal is supplied to a magnetic head 6 through a recording amplifier 4 and a switch circuit 5. A rotary magnetic disc 7 is arranged to be rotated by a spindle motor 8 at a given number of revolution such as 3,600 r.p.m. according to the NTSC system, for example. The spindle motor 8 is provided with a servo circuit 10. When one field portion of a TV signal is recorded for a still picture while the magnetic disc makes one turn, the magnetic head 6 is shifted to another recording track on the disc by a head shifting device 9. A control circuit 11 is arranged to control the above-stated circuits and devices. When a trigger signal is applied to the control circuit 11 from outside, one field portion of the TV signal is recorded on the magnetic disc 7 and then the magnetic head 6 is shifted to a new position by the head shifting device 9 for next recording. These processes are performed under the control of the control circuit 11.
In reproducing an image recorded on the magnetic disc 7, a recording/reproduction selection switch 13 is operated to switch the camera from a recording mode over to a reproducing mode. Then, this time, the output of the magnetic head 6 is produced through a reproduction amplifier 12. In this instance, it is of course possible to use devices provided on the outside of the camera for demodulation of the image signal and for making a display on a CRT or the like. However, the devices for the demodulation, the display, etc. may be arranged within the camera.
With the electronic camera thus arranged to be capable of performing reproduction as well as recording, a recording operation tends to be often attempted while the camera has been left in the reproduction mode by an oversight. In such a case, the operator either misses a good shutter chance or tends to mistake the condition of the camera for being out of order.